Perth will need to overcome the hottest rotation in Australian baseball if it is to return to the ABLCS for the first time since 2015.

The Heat will host Canberra - which boasts the best ERA amongst starters since the start of the year - in a best-of-three semi-final series at Perth Harley-Davidson Ballpark.

Since January 1 the Cavs' starting rotation is 10-2 in 16 games with a 3.46 ERA.

The success has left Canberra manager Michael Collins with a tough choice to make with one of his gun starters to drop out of the rotation and another to be slated for a game three which may not be required.

Brian Grening looks set to take game one with Lake Bachar pipping Frank Gailey for game two, and Steven Kent likely to feature out of the bullpen.

Perth will have its work cut out regardless of which of the quarter starts.

Opposition hitters are averaging just .217 against the Cavs' starting rotation since January 1.

Funnily enough the last team to really get to a Canberra starter was the Heat.

Perth scored 11 runs - six earned - off Jonathon Mottay on New Year's Eve as they produced an ABL record 32 runs.

Mottay is no longer with the Cavs and through January the settled rotation has been stingy.

The Heat also have enjoyed impressive outings from starters so far in 2018.

Perth's starters have a combined ERA 5.11 in January, second behind Canberra.

Alex Boshers, Matt Kennelly and Kyle Simon are the projected starters for the Heat with Nick Veale set to drop from the rotation despite strong recent form.

Perth also enters the best-of-three series with a new look at the top.

The Heat will need to replace Jake Fraley - who scored 50 runs and stole 39 bases this season - after he returned home.

But Perth has plenty of willing contributors.

Luke Hughes has driven in 17 runs across the past month and is hitting .373 since January 1.

Tim Kennelly has a season batting average of .407 with 17 RBIs in 18 games.

While the Heat's bright prospects, including Jesse Williams, Robbie Glendinning, Alex Hall and Ulrich Bojarski have strung together good numbers recently.

Canberra duo Jay Baum and David Kandilas, meanwhile, led the league with 28 hits each in January and will need stopping if Perth is to advance.

THREE QUESTIONS

Can the Cavs' starting rotation be broken? Canberra's starting rotation of Brian Grening, Frank Gailey, Lake Bachar and Steven Kent has been dominant in the month leading up to the playoffs. The Cavs' starters have gone 10-2 with a league-best ERA of 3.46 so far in 2018. Grening has thrown a league-high 30 innings in that time (in just four games) and holds an ERA of 3.30. Gailey is 3-0 with a 2.25 ERA and opposition hitters are averaging just .105 against him. Bachar's ERA is 3.97 since January 1.

How much will the Heat feel the loss of Fraley? Covering the loss of Tampa Bay prospect Fraley is nearly impossible. The Perth lead-off man put up amazing numbers across the season. While nobody expects whoever replaces him at the top to have the same impact, it is vital they produce. Working against the Heat is that, unlike Canberra with Travis Witherspoon replacing Buddy Reed, they have not had a test run of their new look ahead of the playoffs.

Will the young guns shine on a big stage? Perth rookies Jesse Williams, Robbie Glendinning, Ulrich Bojarski and Alex Hall have played a huge role in the second half of the season. Williams, Bojarski and Hall have driven in 15 runs in the Heat's past 17 games, while Glendinning ranks third in the league across the past month with 26 hits. A lot will fall on Perth's veterans but if the future can shine on the big stage, it puts the Heat in a great position.

OUR PREDICTION

Canberra 2-1. There is a lot to like about the Cavs on both sides. Offensively, Jay Baum and David Kandilas have starred, while defensively their starting pitching has been rock solid of late. Perth too are a great team but Canberra enters the slightly hotter team. On the back of their starters going deep, they could be just a little too tough for the Heat to beat.